Background: For instance, forward head posture (FHP), characterized by the forward movement of the head relative to the spine, places significant stress on the neck and upper back muscles, disrupting the biomechanical balance of the body. Objects: The objective of this study was to probe the biomechanical effects of FHP on musculoskeletal health through a relative analysis of 26 adults diagnosed with FHP and 26 healthy controls. Methods: In this study, we evaluated the biomechanical impacts of FHP. Participants adjusted their head positions and underwent muscle strength tests, including electromyography assessments and the Biering-Sørensen test for trunk muscle endurance. Data analysis was conducted using Kinovea (Kinovea) and IBM SPSS software ver. 26.0 (IBM Co.) to compare muscle activities between groups with normal and FHPs. Results: The study shows that individuals with FHP have significantly lower muscle activity, endurance, and spinal extension in the erector spinae compared to those without, highlighting the detrimental effects of FHP on these muscles. Conclusion: This study underscores the impact of FHP on erector spinae function and emphasizes the need for posture correction to enhance musculoskeletal health and guide future research on intervention strategies.